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Java Platform Overview and Packaging practice questions

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Practise Oracle Certified Professional Java SE 17 Developer 1Z0-829 Java Platform Overview and Packaging practice questions — original exam-style scenarios with answer choices, explanations, and analysis of common mistakes.

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20 questionsDomain: Java Platform Overview and Packaging

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What the exam tests

What to know about Java Platform Overview and Packaging

Java Platform Overview and Packaging questions test whether you can apply the concept in context, not just recognise a definition.

How the topic appears in realistic exam-style scenarios.

Which detail in the question changes the correct answer.

How to eliminate plausible but wrong options.

How to connect the question back to the wider exam objective.

Watch out for

Common Java Platform Overview and Packaging exam traps

▸Answering from memory before reading the full scenario.
▸Missing a constraint such as cost, availability, security, scope or command context.
▸Choosing a broad answer when the question asks for the most specific fix.
▸Ignoring why the wrong options are tempting.

Practice set

Java Platform Overview and Packaging questions

20 questions · select your answer, then reveal the explanation

Question 1hardmultiple choice

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A Java 17 application is packaged as a JAR with a Main-Class manifest entry. The JAR is run using 'java -jar app.jar'. However, the application throws a NoClassDefFoundError for a class that is inside the JAR. What is the most likely cause?

Trap 1: The Main-Class manifest entry is incorrect

Incorrect. An incorrect Main-Class manifest entry would cause the JVM to fail to find the main class, leading to a different error or the application not starting at all, not a NoClassDefFoundError for another class.

Trap 2: The classpath is not set

Incorrect. When using 'java -jar', the classpath is ignored; the JVM reads the JAR as the sole source of classes. Therefore, not setting the classpath does not cause this error.

Study all Java Platform Overview and Packaging common traps →

A
The class is not exported from its module
Correct. If the class is in a package that is not exported by its module, classes from other modules (including the unnamed module) cannot load it, resulting in NoClassDefFoundError. This is a common issue in modular applications.
B
The Main-Class manifest entry is incorrect
Why wrong: Incorrect. An incorrect Main-Class manifest entry would cause the JVM to fail to find the main class, leading to a different error or the application not starting at all, not a NoClassDefFoundError for another class.
C
The JAR file is corrupt
Correct. A corrupt JAR file prevents the JVM from reading the class bytes, causing NoClassDefFoundError even though the class is listed in the JAR. This is a plausible cause when the JAR is damaged.
D
The classpath is not set
Why wrong: Incorrect. When using 'java -jar', the classpath is ignored; the JVM reads the JAR as the sole source of classes. Therefore, not setting the classpath does not cause this error.

Full breakdown with real-world context →

Question 2mediummultiple choice

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A company uses CI/CD to build and package a Java 17 application. They want to produce a single executable JAR that includes all dependencies. Which tool should be used to achieve this?

Trap 1: Maven JAR Plugin

Maven JAR Plugin creates a standard JAR without dependencies.

Trap 2: Java jar command

The jar command packages files but does not resolve dependencies.

Trap 3: jlink tool

jlink creates a custom runtime image, not an executable JAR.

Study all Java Platform Overview and Packaging common traps →

A
Maven JAR Plugin
Why wrong: Maven JAR Plugin creates a standard JAR without dependencies.
B
Maven Shade Plugin
Maven Shade Plugin creates an uber-JAR with all dependencies.
C
Java jar command
Why wrong: The jar command packages files but does not resolve dependencies.
D
jlink tool
Why wrong: jlink creates a custom runtime image, not an executable JAR.

Full breakdown with real-world context →

Question 3easymultiple choice

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A developer has a module named 'com.example.app' that exports a package 'com.example.api'. Another module 'com.example.client' requires 'com.example.app'. Which directive must be in the module-info.java of 'com.example.client'?

Trap 1: opens com.example.app;

'opens' is for reflective access.

Trap 2: uses com.example.api;

'uses' is for service interfaces.

Trap 3: exports com.example.api;

Exports are used in the providing module, not the client.

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A
opens com.example.app;
Why wrong: 'opens' is for reflective access.
B
uses com.example.api;
Why wrong: 'uses' is for service interfaces.
C
exports com.example.api;
Why wrong: Exports are used in the providing module, not the client.
D
requires com.example.app;
This correctly declares the dependency.

Full breakdown with real-world context →

Question 4hardmultiple choice

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A Java 17 application is deployed on a server. The application uses modules but one required module is missing from the module path. Which exception will be thrown at startup?

Trap 1: ExceptionInInitializerError

ExceptionInInitializerError is thrown when a static initializer fails, not due to a missing module at startup.

Trap 2: NoClassDefFoundError

NoClassDefFoundError occurs when a class that was available at compile time is missing at runtime, not during module resolution.

Trap 3: ClassNotFoundException

ClassNotFoundException is thrown when an application tries to load a class by name, not for module resolution.

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A
ExceptionInInitializerError
Why wrong: ExceptionInInitializerError is thrown when a static initializer fails, not due to a missing module at startup.
B
NoClassDefFoundError
Why wrong: NoClassDefFoundError occurs when a class that was available at compile time is missing at runtime, not during module resolution.
C
ClassNotFoundException
Why wrong: ClassNotFoundException is thrown when an application tries to load a class by name, not for module resolution.
D
ModuleNotFoundException
ModuleNotFoundException is not a standard Java exception; the correct exception is java.lang.module.FindException.

Full breakdown with real-world context →

Question 5mediummultiple choice

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A development team wants to ensure that a Java 17 application runs with a specific set of modules. They want to minimize the footprint by including only necessary modules. Which tool should they use?

Trap 1: javac

javac compiles Java source code.

Trap 2: jmod

jmod creates JMOD files for packaging, not runtime images.

Trap 3: jar

jar packages classes, it does not create a runtime.

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A
javac
Why wrong: javac compiles Java source code.
B
jlink
jlink assembles a custom runtime image with specified modules.
C
jmod
Why wrong: jmod creates JMOD files for packaging, not runtime images.
D
jar
Why wrong: jar packages classes, it does not create a runtime.

Full breakdown with real-world context →

Question 6mediummulti select

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Which TWO statements are true about Java modules in Java 17? (Choose two.)

Trap 1: All packages in a module are automatically exported.

Only explicitly exported packages are accessible outside the module.

Trap 2: The jdeps tool can be used to create a module graph.

jdeps analyzes dependencies but does not create graphs directly.

Trap 3: The jlink tool creates a JAR file containing the module.

jlink creates a runtime image, not a JAR.

Study all Java Platform Overview and Packaging common traps →

A
A module can export a package only to specific modules using 'exports ... to ...'
Qualified exports limit access to specified modules.
B
The module-info.java file must be compiled with javac and placed in the root of the JAR.
module-info.class must be at the root of the modular JAR.
C
All packages in a module are automatically exported.
Why wrong: Only explicitly exported packages are accessible outside the module.
D
The jdeps tool can be used to create a module graph.
Why wrong: jdeps analyzes dependencies but does not create graphs directly.
E
The jlink tool creates a JAR file containing the module.
Why wrong: jlink creates a runtime image, not a JAR.

Full breakdown with real-world context →

Question 7hardmulti select

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Which THREE are valid ways to package a Java 17 application for distribution? (Choose three.)

Trap 1: ZIP file containing compiled classes

ZIP is not a standard Java packaging format.

Trap 2: Shell script that compiles and runs the application

That is not a packaging format.

Study all Java Platform Overview and Packaging common traps →

A
JMOD file
JMOD is a packaging format for modules.
B
ZIP file containing compiled classes
Why wrong: ZIP is not a standard Java packaging format.
C
Native installer (e.g., MSI, DMG)
jpackage can create native installers.
D
Shell script that compiles and runs the application
Why wrong: That is not a packaging format.
E
JAR file with a manifest
Standard JAR packaging is valid.

Full breakdown with real-world context →

Question 8easymultiple choice

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A developer runs 'java --list-modules' and sees the output above. Which command can be used to create a custom runtime image containing only the 'java.base' module?

Network Topology

Trap 1: jar --create --file myimage --module java.base

jar does not create runtime images.

Trap 2: jimage --add-modules java.base --output myimage

jimage is for managing runtime images, not creating them.

Trap 3: jlink --modules java.base --output myimage

--modules is not a valid flag.

Study all Java Platform Overview and Packaging common traps →

A
jar --create --file myimage --module java.base
Why wrong: jar does not create runtime images.
B
jimage --add-modules java.base --output myimage
Why wrong: jimage is for managing runtime images, not creating them.
C
jlink --modules java.base --output myimage
Why wrong: --modules is not a valid flag.
D
jlink --add-modules java.base --output myimage
Correct syntax for jlink.

Full breakdown with real-world context →

Question 9mediummultiple choice

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A developer receives the above error when running a modular Java application. What is the most likely cause?

Exhibit

Refer to the exhibit.

```
Error: Unable to initialize main class com.example.Main
Caused by: java.lang.module.ResolutionException: Module com.example.app not found
```

Trap 1: The module-info.java has a syntax error.

A syntax error would be caught at compile time.

Trap 2: The JRE version is too old.

If the JRE were too old, it would not support modules at all.

Trap 3: The main class is misspelled.

That would cause a different error (ClassNotFoundException).

Study all Java Platform Overview and Packaging common traps →

A
The module-info.java has a syntax error.
Why wrong: A syntax error would be caught at compile time.
B
The module 'com.example.app' is not on the module path.
The error indicates the module was not found.
C
The JRE version is too old.
Why wrong: If the JRE were too old, it would not support modules at all.
D
The main class is misspelled.
Why wrong: That would cause a different error (ClassNotFoundException).

Full breakdown with real-world context →

Question 10hardmultiple choice

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A company runs a Java 17 microservice that reads stock market data from a WebSocket and processes it. The application is packaged as an executable JAR using Maven Shade Plugin. Recently, after a dependency update, the application started throwing 'javax.net.ssl.SSLHandshakeException: PKIX path building failed' when connecting to the WebSocket. The security team insists that no certificates should be imported into the default truststore. The application already includes a custom truststore file 'certs.jks' in the resources folder. The developer had been loading it programmatically but the new dependency uses a different SSL context. The application must trust the WebSocket server without modifying JVM defaults. Which action should be taken?

Trap 1: Add the certificate to the default truststore using keytool and…

The security team prohibits modifying the default truststore.

Trap 2: Use the jlink tool to create a custom runtime image that includes…

jlink does not handle truststore configuration; certificates still need to be placed.

Trap 3: Create a custom TrustManager that bypasses all certificate…

This would compromise security and is not a best practice.

Study all Java Platform Overview and Packaging common traps →

A
Set the system property 'javax.net.ssl.trustStore' to the path of 'certs.jks' and 'javax.net.ssl.trustStorePassword' to its password.
This tells the JVM to use the custom truststore globally.
B
Add the certificate to the default truststore using keytool and restart the application.
Why wrong: The security team prohibits modifying the default truststore.
C
Use the jlink tool to create a custom runtime image that includes the certificate.
Why wrong: jlink does not handle truststore configuration; certificates still need to be placed.
D
Create a custom TrustManager that bypasses all certificate validation.
Why wrong: This would compromise security and is not a best practice.

Full breakdown with real-world context →

Question 11easymulti select

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Which TWO statements are true about the Java Platform Module System (JPMS) introduced in Java 9?

Trap 1: The module path is searched after the class path when resolving…

The module path and class path are separate; the class path is used for unnamed module and the module path for named modules.

Trap 2: An automatic module is one that has a module-info.class file at its…

An automatic module is created from a JAR placed on the module path without a module-info.class.

Trap 3: A named module can access the unnamed module without any explicit…

Named modules are not allowed to read the unnamed module unless the --add-reads flag is used.

Study all Java Platform Overview and Packaging common traps →

A
The module path is searched after the class path when resolving types.
Why wrong: The module path and class path are separate; the class path is used for unnamed module and the module path for named modules.
B
The module declaration is stored in a file named module-info.java.
The module declaration is placed in module-info.java, which is compiled to module-info.class.
C
A module must explicitly export a package to make it accessible to other modules.
By default, a package is not exported; it must be declared with the exports directive.
D
An automatic module is one that has a module-info.class file at its root.
Why wrong: An automatic module is created from a JAR placed on the module path without a module-info.class.
E
A named module can access the unnamed module without any explicit declaration.
Why wrong: Named modules are not allowed to read the unnamed module unless the --add-reads flag is used.

Full breakdown with real-world context →

Question 12mediummultiple choice

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A developer runs the command above on a JAR file. Which statement accurately describes the module myapp?

Network Topology

Trap 1: The module opens com.myapp.internal for deep reflection to all…

The command shows 'exports ... to', not 'opens'. Deep reflection requires the opens directive.

Trap 2: The module provides a service implementation.

No 'provides' directive is present in the module descriptor.

Trap 3: The module requires java.base explicitly; it is not mandated.

java.base is always implicitly required and mandated; it does not need to be declared.

Study all Java Platform Overview and Packaging common traps →

A
The module opens com.myapp.internal for deep reflection to all modules.
Why wrong: The command shows 'exports ... to', not 'opens'. Deep reflection requires the opens directive.
B
The module provides a service implementation.
Why wrong: No 'provides' directive is present in the module descriptor.
C
The module exports com.myapp.internal to the module myapp.tests only.
The qualified exports directive restricts access to the specified module.
D
The module requires java.base explicitly; it is not mandated.
Why wrong: java.base is always implicitly required and mandated; it does not need to be declared.

Full breakdown with real-world context →

Question 13hardmultiple choice

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A team is developing a large enterprise application using Java 17. The application consists of multiple modules: core (provides logging and configuration), services (business logic), and web (REST endpoints). The modules are packaged as separate JAR files and deployed on a server. During runtime, the web module throws a java.lang.ClassNotFoundException for a class that is part of the core module. The core module's module-info.java exports the package containing the missing class. The web module's module-info.java requires core. However, the services module also needs the same class but uses a different version of it, causing conflicts. The team decides to use the class path for the conflicting package and the module path for the rest. They add the conflicting JAR to the class path and keep the other JARs on the module path. After this change, the web module still cannot find the class, but the services module works fine. What is the most likely cause of the issue?

Trap 1: The services module is using an automatic module, which…

Even if the services module were automatic, the web module being named still cannot access the class path package if it is split.

Trap 2: The class path is not scanned for JAR files unless the module path…

The class path is always scanned for classes, but named modules cannot access classes from the class path if the package is split.

Trap 3: The core module's module-info.java does not export the package to…

The export to all modules should allow the web module to access it, but the issue is the split package, not the export.

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A
The services module is using an automatic module, which automatically reads the unnamed module, while the web module is a named module that does not.
Why wrong: Even if the services module were automatic, the web module being named still cannot access the class path package if it is split.
B
The class path is not scanned for JAR files unless the module path is empty.
Why wrong: The class path is always scanned for classes, but named modules cannot access classes from the class path if the package is split.
C
The web module is a named module and cannot access classes from a split package that is also in the unnamed module.
The module system prevents named modules from accessing split packages from the class path to maintain reliable configuration.
D
The core module's module-info.java does not export the package to the web module; it only exports it to all modules.
Why wrong: The export to all modules should allow the web module to access it, but the issue is the split package, not the export.

Full breakdown with real-world context →

Question 14mediummulti select

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Which TWO statements about the Java Platform Module System (JPMS) are true? (Choose two.)

Trap 1: All classes on the classpath are automatically placed in the boot…

Incorrect: Classes on the classpath belong to the unnamed module, not the boot layer.

Trap 2: A module declaration is placed in a file named module-info.class.

Incorrect: The declaration is in module-info.java, compiled to module-info.class.

Trap 3: JPMS allows the use of the classpath to add modules to the module…

Incorrect: Modules are placed on the module path, not the classpath.

Study all Java Platform Overview and Packaging common traps →

A
All classes on the classpath are automatically placed in the boot layer.
Why wrong: Incorrect: Classes on the classpath belong to the unnamed module, not the boot layer.
B
JPMS provides reliable configuration through explicit module dependencies.
Correct: JPMS requires modules to declare dependencies explicitly, eliminating classpath issues.
C
A module declaration is placed in a file named module-info.class.
Why wrong: Incorrect: The declaration is in module-info.java, compiled to module-info.class.
D
JPMS allows the use of the classpath to add modules to the module graph.
Why wrong: Incorrect: Modules are placed on the module path, not the classpath.
E
JPMS supports strong encapsulation by controlling which packages are accessible to other modules.
Correct: JPMS restricts access to packages unless they are exported.

Full breakdown with real-world context →

Question 15hardmultiple choice

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Given the output of `java --list-modules` from a Java 17 installation, which module is NOT included by default when using the `--release 17` flag with `javac`?

Network Topology

Trap 1: jdk.jfr

Incorrect: jdk.jfr is a JDK-specific module but is included with --release 17.

Trap 2: java.net.http

Incorrect: java.net.http is a standard module included with --release 17.

Trap 3: java.sql

Incorrect: java.sql is a standard module included with --release 17.

Study all Java Platform Overview and Packaging common traps →

A
jdk.jfr
Why wrong: Incorrect: jdk.jfr is a JDK-specific module but is included with --release 17.
B
jdk.incubator.foreign
Correct: Incubator modules are not included when using --release.
C
java.net.http
Why wrong: Incorrect: java.net.http is a standard module included with --release 17.
D
java.sql
Why wrong: Incorrect: java.sql is a standard module included with --release 17.

Full breakdown with real-world context →

Question 16easymultiple choice

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A development team is working on a Java 17 application that must be packaged as a custom runtime image for deployment on a Linux server without a JDK installed. The application uses `java.base`, `java.logging`, and `java.sql` modules, and also requires the `jdk.crypto.cryptoki` module for hardware security module (HSM) integration. The team wants to minimize the image size while ensuring all necessary modules are included. They run `jlink --add-modules java.base,java.logging,java.sql,jdk.crypto.cryptoki --output myapp-runtime`. The resulting image runs the application but fails at startup with a `ClassNotFoundException` for `javax.crypto.spec.SecretKeySpec`. Which action should the team take to resolve the issue?

Trap 1: Manually add the `java.security.jgss` module to the `--add-modules`…

Incorrect: SecretKeySpec is in java.base; adding jgss is not the direct fix.

Trap 2: Use the `--list-modules` option with jlink to verify which modules…

Incorrect: This is a diagnostic step but not the action that resolves the issue; the team needs to include the missing services.

Trap 3: Add `ALL-MODULE-PATH` to the `--add-modules` list to include all…

Incorrect: This would include all modules, defeating the purpose of minimizing image size.

Study all Java Platform Overview and Packaging common traps →

A
Manually add the `java.security.jgss` module to the `--add-modules` list.
Why wrong: Incorrect: SecretKeySpec is in java.base; adding jgss is not the direct fix.
B
Use the `--list-modules` option with jlink to verify which modules are included, then add any missing ones.
Why wrong: Incorrect: This is a diagnostic step but not the action that resolves the issue; the team needs to include the missing services.
C
Add `ALL-MODULE-PATH` to the `--add-modules` list to include all available modules.
Why wrong: Incorrect: This would include all modules, defeating the purpose of minimizing image size.
D
Add `--bind-services` to the jlink command to include service provider modules.
Correct: --bind-services links service provider modules required by the specified modules, which may include necessary crypto implementations.

Full breakdown with real-world context →

Question 17mediumdrag order

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Arrange the steps to read a file using NIO.2 Files.lines() in Java.

Drag steps to the numbered slots on the right, or tap a step then tap a slot.

Steps

Order

1Step 1

2Step 2

3Step 3

4Step 4

5Step 5

Trap 1: 1

This is incorrect because Files.lines() expects a Path, not a string literal. Also, the stream is opened before the Path is created, which is logically backward.

Trap 2: 1

This is incorrect because processing the stream before obtaining it is impossible; the stream must be obtained first to perform any operations.

Trap 3: 1

This is incorrect because closing the stream before processing it makes the stream unavailable for reading, resulting in a 'stream closed' exception.

Study all Java Platform Overview and Packaging common traps →

A
1. Create a Path object using Paths.get("file.txt"). 2. Call Files.lines(path) to obtain a Stream<String>. 3. Process the stream using stream operations like forEach, filter, etc. 4. Close the stream by calling close() or using try-with-resources.
This is the correct order because Files.lines() requires a Path, returns a lazily populated Stream, and the stream must be closed to release file handles, typically after processing.
B
1. Call Files.lines("file.txt") directly with a string. 2. Create a Path object. 3. Process the stream. 4. Close the stream.
Why wrong: This is incorrect because Files.lines() expects a Path, not a string literal. Also, the stream is opened before the Path is created, which is logically backward.
C
1. Create a Path object. 2. Process the stream (e.g., apply operations). 3. Call Files.lines(path) to get the stream. 4. Close the stream.
Why wrong: This is incorrect because processing the stream before obtaining it is impossible; the stream must be obtained first to perform any operations.
D
1. Create a Path object. 2. Call Files.lines(path) to get the stream. 3. Close the stream. 4. Process the stream.
Why wrong: This is incorrect because closing the stream before processing it makes the stream unavailable for reading, resulting in a 'stream closed' exception.

Full breakdown with real-world context →

Question 18mediummatching

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Match each Java 17 feature to its description.

Drag a concept onto its matching description — or click a concept then click the description.

Concepts

Matches

Restricts which classes can extend or implement a type

Allows patterns in case labels for type checks and destructuring

Transparent carriers for immutable data

Multi-line string literals with automatic formatting

Switch that can be used as an expression and returns a value

Trap 1: Enhanced NullPointerExceptions: A feature that allows a class to…

Incorrect – Enhanced NullPointerExceptions (Java 14) precisely describe which variable was null, not inheritance restriction. This definition actually describes Sealed Classes.

Trap 2: Switch Expressions: A preview feature that allows testing an…

Incorrect – Switch Expressions are a standard feature since Java 14, not a preview. The description refers to Pattern Matching for switch (preview in Java 17).

Study all Java Platform Overview and Packaging common traps →

A
Sealed Classes: A feature that allows a class or interface to restrict which other classes or interfaces may extend or implement it.
Sealed classes, finalized in Java 17, enable controlled inheritance by specifying permitted subclasses.
B
Records: A feature that provides a compact syntax for declaring classes that are transparent holders for immutable data.
Records, standardized in Java 16, automatically generate constructor, accessors, equals, hashCode, and toString for immutable data carriers.
C
Pattern Matching for switch (Preview): A preview feature that allows switch expressions and statements to test an expression against a pattern, enabling more concise and safe code.
Pattern matching for switch (JEP 406) is a preview in Java 17, allowing patterns in case labels to extract components and simplify code.
D
Text Blocks: A feature that allows multi-line string literals with automatic indentation and escape handling.
Text blocks, finalized in Java 15, simplify the writing of multi-line strings by managing indentation and escape sequences.
E
Enhanced NullPointerExceptions: A feature that allows a class to restrict which subclasses can implement it.
Why wrong: Incorrect – Enhanced NullPointerExceptions (Java 14) precisely describe which variable was null, not inheritance restriction. This definition actually describes Sealed Classes.
F
Switch Expressions: A preview feature that allows testing an expression against a pattern using switch.
Why wrong: Incorrect – Switch Expressions are a standard feature since Java 14, not a preview. The description refers to Pattern Matching for switch (preview in Java 17).

Full breakdown with real-world context →

Question 19easymultiple choice

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A developer has written a Java class that uses external libraries packaged as JAR files. The application runs correctly when launched from an IDE but fails with a ClassNotFoundException when run from the command line using `java -cp`. What is the most likely cause?

Trap 1: The classpath is missing the directory containing the class files.

The class files directory is usually included, but the issue is missing JARs.

Trap 2: The JAR files are not in the module path.

Module path is for modular JARs; non-modular JARs go on classpath.

Trap 3: The Java command should use java -jar instead.

java -jar is only for executable JARs with a manifest; doesn't fix ClassNotFoundException.

Study all Java Platform Overview and Packaging common traps →

A
The JAR files are not listed in the classpath argument.
The classpath must explicitly list all required JAR files.
B
The classpath is missing the directory containing the class files.
Why wrong: The class files directory is usually included, but the issue is missing JARs.
C
The JAR files are not in the module path.
Why wrong: Module path is for modular JARs; non-modular JARs go on classpath.
D
The Java command should use java -jar instead.
Why wrong: java -jar is only for executable JARs with a manifest; doesn't fix ClassNotFoundException.

Full breakdown with real-world context →

Question 20mediummultiple choice

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A team is migrating a large monolithic Java 8 application to Java 17 using modules. They want to ensure that only the required packages are exported. Which tool should they use to analyze current dependencies and generate module descriptors?

Trap 1: jlink

jlink creates a runtime image, not for dependency analysis.

Trap 2: javap

javap disassembles class files, does not analyze dependencies.

Trap 3: jar

jar is for creating and manipulating JAR files, not for dependency analysis.

Study all Java Platform Overview and Packaging common traps →

A
jlink
Why wrong: jlink creates a runtime image, not for dependency analysis.
B
javap
Why wrong: javap disassembles class files, does not analyze dependencies.
C
jar
Why wrong: jar is for creating and manipulating JAR files, not for dependency analysis.
D
jdeps
jdeps analyzes dependencies and can generate module-info.java suggestions.

Full breakdown with real-world context →

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Every question in these sessions is drawn from the Java Platform Overview and Packaging domain — nothing else.

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Frequently asked questions

What does the 1Z0-829 exam test about Java Platform Overview and Packaging?: Java Platform Overview and Packaging questions test whether you can apply the concept in context, not just recognise a definition.
How should I use these practice questions?: Select your answer before revealing the explanation. Then read why each option is right or wrong — this active recall approach builds retention far faster than re-reading notes.
Can I practise just Java Platform Overview and Packaging questions in a focused session?: Yes — the session launcher on this page draws every question from the Java Platform Overview and Packaging domain. Use a 10-question session first to gauge your baseline, then move to 20 or 30 once the weak spots are clear.
Where can I practise other 1Z0-829 topics?: Use the topic links above to move to related areas, or go back to the 1Z0-829 question bank to see all topics.
Are these real exam questions or dumps?: These are original practice questions written to test the same concepts the 1Z0-829 exam covers. They are not copied from any real exam or dump site.

Java Platform Overview and Packaging only

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Mixed 1Z0-829 session

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All 1Z0-829 questions Java Platform Overview and Packaging domain overview 1Z0-829 exam guide

Exam traps to avoid

▸Answering from memory before reading the full scenario.
▸Missing a constraint such as cost, availability, security, scope or command context.
▸Choosing a broad answer when the question asks for the most specific fix.
▸Ignoring why the wrong options are tempting.

Java Platform Overview and Packaging practice questions

What to know about Java Platform Overview and Packaging

Common Java Platform Overview and Packaging exam traps

Java Platform Overview and Packaging questions

A Java 17 application is packaged as a JAR with a Main-Class manifest entry. The JAR is run using 'java -jar app.jar'. However, the application throws a NoClassDefFoundError for a class that is inside the JAR. What is the most likely cause?

A company uses CI/CD to build and package a Java 17 application. They want to produce a single executable JAR that includes all dependencies. Which tool should be used to achieve this?

A developer has a module named 'com.example.app' that exports a package 'com.example.api'. Another module 'com.example.client' requires 'com.example.app'. Which directive must be in the module-info.java of 'com.example.client'?

A Java 17 application is deployed on a server. The application uses modules but one required module is missing from the module path. Which exception will be thrown at startup?

A development team wants to ensure that a Java 17 application runs with a specific set of modules. They want to minimize the footprint by including only necessary modules. Which tool should they use?

Which TWO statements are true about Java modules in Java 17? (Choose two.)

Which THREE are valid ways to package a Java 17 application for distribution? (Choose three.)

A developer runs 'java --list-modules' and sees the output above. Which command can be used to create a custom runtime image containing only the 'java.base' module?

A developer receives the above error when running a modular Java application. What is the most likely cause?

Exhibit

Which TWO statements are true about the Java Platform Module System (JPMS) introduced in Java 9?

A developer runs the command above on a JAR file. Which statement accurately describes the module myapp?

Which TWO statements about the Java Platform Module System (JPMS) are true? (Choose two.)

Given the output of `java --list-modules` from a Java 17 installation, which module is NOT included by default when using the `--release 17` flag with `javac`?

Arrange the steps to read a file using NIO.2 Files.lines() in Java.

Match each Java 17 feature to its description.

A developer has written a Java class that uses external libraries packaged as JAR files. The application runs correctly when launched from an IDE but fails with a ClassNotFoundException when run from the command line using `java -cp`. What is the most likely cause?

A team is migrating a large monolithic Java 8 application to Java 17 using modules. They want to ensure that only the required packages are exported. Which tool should they use to analyze current dependencies and generate module descriptors?

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